Tracking the amyloidogenic core of IAPP amyloid fibrils: Insights from micro-Raman spectroscopy.

Human islet amyloid polypeptide (hIAPP) is the major protein component of extracellular amyloid deposits, located in the islets of Langerhans, a hallmark of type II diabetes. The underlying mechanisms of IAPP aggregation have not yet been clearly defined, although the highly amyloidogenic sequence of the protein has been extensively studied. Several segments have been highlighted as aggregation-prone regions (APRs), with much attention focused on the central 8-17 and 20-29 stretches.

Complexation of lysozyme with poly(sodium(sulfamate-carboxylate)isoprene).

The complexation between hen egg white lysozyme (HEWL) and a novel pH-sensitive and intrinsically hydrophobic polyelectrolyte poly(sodium(sulfamate-carboxylate)isoprene) (SCPI), was investigated by means of dynamic, static, and electrophoretic light scattering and isothermal titration calorimetry measurements. The complexation process was studied at both pH 7 and 3 (high and low charge density of the SCPI, respectively) and under low ionic strength conditions for two polyelectrolyte samples of different molecular weights. The solution behavior, structure, and effective charge of the formed complexes proved to be dependent on the pH, the [-]/[+] charge ratio, and the molecular weight of the polyelectrolyte.

Non-contact detection of ciprofloxacin in a model anterior chamber using Raman spectroscopy.

We examine the application of an improved noncontact and noninvasive Raman spectroscopic technique in measuring medicines at therapeutic concentrations in a model system mimicking the anterior chamber of the eye. A 90-deg laser Raman scattering geometry is employed to reduce the direct exposure of the basic cordial ocular tissues to the laser beam and increase the signal-to-noise ratio of the spectra. The technique is applied to a commercially available artificial anterior chamber (AAC) fitted with corneas of porcine eyes.

Molecular interactions between dimethoxycurcumin and Pamam dendrimer carriers.

Dimethoxycurcumin, a lipophilic analog of curcumin found as a major pigment in the Indian species turmeric (Curcuma longa Linn.), is known to possess significant activity against various cancer cell lines, but its use as an anticancer drug is hindered by its poor water solubility. The conjugation of dimethoxycurcumin to water-soluble PAMAM dendrimers (generations 3.

Dogfish egg case structural studies by ATR FT-IR and FT-Raman spectroscopy.

The dogfish egg case is a composite structure that combines mechanical tensile strength, toughness and elasticity with high permeability to small molecules and ions. Presumably, it provides both a protective and a filtering role for the egg/embryo contained within it. In this work, we performed structural studies of the Galeus melastomus egg case at two different stages of the hardening process, utilizing ATR FT-IR and FT-Raman spectroscopy.

Amyloid fibril formation propensity is inherent into the hexapeptide tandemly repeating sequence of the central domain of silkmoth chorion proteins of the A-family.

Peptide-analogues of the A and B families of silkmoth chorion proteins form amyloid fibrils under a variety of conditions [Iconomidou, V.A., Vriend, G.

FT-Raman spectroscopy as diagnostic tool of Congo red binding to amyloids.

Chorion is the major component of silkmoth eggshell. More than 95% of its dry mass consists of the A and B families of low molecular weight structural proteins, which have remarkable mechanical and chemical properties protecting the oocyte and developing embryo from environmental hazards. We present data from FT-Raman spectroscopy of silkmoth chorion and amyloid-like fibrils formed from peptide analogues of chorion proteins, both unstained and stained by Congo red.